Dive into the ocean depths with legendary underwater photojournalist and National Geographic explorer Brian Skerry as he shares recent photographs and stories about one of the most fascinating and threatened creatures on the planet: the shark.

The National Geographic Live series brings thought-provoking presentations by today’s leading explorers, scientists, photographers, and performing artists right to you. Each presentation is filmed in front of a live audience at National Geographic headquarters in Washington, D.C.

So the first story that I wanted to share of this new work is a story about Tiger Sharks. Now, Tiger Sharks if you read the literature are described as the most dangerous sharks in tropical waters. They are considered the second most dangerous species of shark overall after The Great White. They've certainly been portrayed as mindless monsters but in reality the cutting edge science that's being done right now is showing that these are animals that actually have a pretty high degree of cognition and they have the ability to learn and the ability to remember. Can't get into all that right now but this is some of the stuff that will be published I think in the time ahead. They're also one of the most versatile species of sharks. One day they'll be hunting in a thousand meters of deep Pacific water and the very next day they'll be in a marina looking for fish scraps under a fisherman's boat. When they are born tiger sharks look like this, they have this amazingly stunning pattern of stripes which off course is where they get the name from, the tiger like stripes that they have on their body. This was a neonate just a few days old that I photographed in Hawaii last year. Those stripes begin to fade as the animal gets a little bit older and they're not quite as vivid and quite striking. But the in 20 years or so, I've been diving for almost 40 years, but for about 20 years of my career, I was very interested in finding tiger sharks but had almost no success. I would do trips to various places but never really found them in any predictable way but a number of years ago a buddy of mine that ran or runs a dive business out of Palm Beach Florida discovered a place in the Bahamas, in the Northern Bahamas that he named Tiger Beach. And this is an aerial view, I used the National Geographic blimp to do a low altitude aerial shot here. And this is a place, it's sort of a sandy, shallow, sand flat area in the Northern Bahamas where these animals congregate, you'll find on any given day, a dozen or more of them. So we see a bunch of these big ol' tigers hanging out behind the boat, perfect day to go swimming. As we see right here. This is what it looks like underwater, this is the scene underwater. You can swim down about maybe 20 feet or so and find yourself in the company of these big tiger sharks. Many of these are between 12 and 14 feet in length. And they'll come up very close, they'll give you some great closeup encounters not using any cages here or anything. And it's a pretty extraordinary thing to be able to see these animals like this and to be in their presence. The first time I did it, my heart was racing through my chest but over time, you never fully let your guard down but I think you relax at least a little bit to some extent. Part of the approach that I took this time when I was out there for this latest story in the magazine was, to try to show these animals, a little bit like their terrestrial namesake, to try to make pictures that looked a little bit like a tiger on land maybe sneaking its way through the grasses of India or something, channeling my inner Steve Winter here. But the difference was off course I wasn't on the back of an elephant. So you have be eye to eye with these guys. And that's what some people like to do, you like to just have a little conversation with tiger sharks, just how was your day, kinda have a little chat here like this diver's doing. Actually this is showing the fact that ecotourism has really prospered in this place, ever since the discovery of Tiger Beach, a number of companies have sprung up. Ecotourism dive companies that will get you out there and get you in the company of tiger sharks, like we see right here. Sometimes it can get a little dicey, especially when you get multiple sharks coming around but, in my experiences out there in the weeks that I've spent out in Tiger Beach, I have to say that they were all very well behaved, generally well behaved for the most part. Occasionally, they'll try to eat my camera, like this one did right here but, once they realize that it's not especially tasty, they sort of just move on. And during my time out there on these recent trips, I also wanted to move away from those shallow, sandy places, Tiger Beach proper. And try to photograph tiger sharks out in the deeper reefs. Because they hang out there too. Lots of tigers in the Bahamas and I wanted to see if I could get the lord of reef sort of patrolling over these sponges and corals that we see here. Or to look at the behaviors of multiple animals. We do see a lot of different sharks here and there there definitely seems to be sort of some hierarchy, some social behavior. It's not fully understood, I mean to some degree, it's usually the big shark wins, the other one usually goes the other way but, there is something going on there that I think we'll figure out in time. And we see this a lot too. Sharks with hooks in their mouth. And it's not relegated only to tiger sharks, pretty much everywhere I go in the world, you see evidence of fishing pressure. This tiger had two big hooks in its mouth but we see jewelry as it's often called on many sharks all over the world. It's a very troubling trend that seems to be happening everywhere. And thanks to a grant from the National Geographic Society on these latest projects, we were also able to fund some research out there. This is, on the right of the frame, this is Dr. Neil Hammerschlag from the University of Miami who's been studying tiger sharks in this region for some time and one of the ways he does this is he built this special platform that can submerge just below the back of our boat, you tie it up to the back of the boat, and then he brings a Tiger shark in and I'm not sure his insurance company is seeing these pictures but nonetheless, what could go wrong. And he brings it in and then they work up the shark, they do some science here. But the standard procedure has always been to measure the shark, take a DNA clipping, maybe a fin clipping for DNA sample, they tag the shark usually, sometimes that's done surgically, they implant a body cavity tag so they can track the animal over time. But some of the newest research is ultrasound work that's going on right here and that's what this woman researcher is doing in the center of the frame here with the goggles. Because Tiger Beach, it's been discovered, seems to be a maternity ward. Most of the sharks there are females and many of them are pregnant and that shallow warm water seems to promote gestation. So they're doing these sonograms that they can keep a videograph of and they can see how many pups are inside and then the tagging data will show where the animal goes, they don't actually have their pups in the Bahamas, they're going up into Northern Florida, Georgia water, so in terms of conservation, this would be a very critical habitat, we might want to protect in the future. And we also did some criticam work. I think most of you might know about National Geographic's crittercam where they attach cameras and various scientific instruments to animals and let them sort of carry it and then it pops off. This was the first time that one had been attached and deployed underwater. So this is Neil Hammerschlag after he just put that thin clamp on the tiger shark here and he's sort of checking it, making sure it's alright. And then off it goes for the better part of the day recording both video and all kinds of other data. And here we can see the shark sort of swimming around a little shark cameraman. Here just another example of an animal taking our jobs. But in any case, what this data, I mean they only did it a little bit while we were out there but it did yield some interesting things. Most of the ecotourism operators that are out there felt that they knew exactly what these sharks were doing. They go in from one operator to the next, and just staying on that shallow area. But the crittercam showed that in between some of those visits, they're making these very deep dives. We don't quite know exactly what's happening down there but clearly there's a lot more going on in these animal's lives than we realize. So here's a little video that I wanted to share behind the scenes, just a short video. I thought, okay. just give you a sense of what it's like to be down there with those giant animals and it can be a little unnerving at times but as I said it's all been pretty good. So this, for that same story on Tiger sharks, I also worked in South Africa. This is a photo my assistant made of me on assignment here with a tiger shark up in the water column and this site is a new site that was sort of discovered by a researcher named Dr. Rian Dailey, it's up near the Mozambique border. And what Rian Dailey found is that there's a deep water reef there that tiger sharks seem to frequent, but if we dive in the shallow waters just below the surface, Tigers will often rise up and sort of check us out and he's just beginning his research out there to find out what these animals are doing, where they're going and so forth. But he invited me to come out and it was a chance for me to make pictures in a sort of different environment, instead of being on the bottom. But these are completely wild sharks, they're not acclimated or habituated to humans whatsoever. Very very wild and you're definitely part of the food chain when you're out there. And online Tiger Beach, you can't stand on the bottom, you don't have that sort of safety blanket of being able to stand on the bottom. So you're really kind of out there. But I have another little video that shows what we were doing out here. I was living at a coastal jungle and going out everyday in an inflatable so this is about a two minute video. So lots more work to do in South Africa. So these are just a few frames that I made of those sharks and again they have sort of a different look up in the blue water there, big beefy sharks. A little bit unnerving when they come real close to you but you know it's stunning seeing this was one that was just covered in remoras adorned in remoras, and it's actually a silver tip shark in the bottom right of the frame. There were many other species out there, dusky sharks and bull sharks, but it was the tigers off course that I was interested in but one sort of turning it. And it's one of those things where you're in the water out there you wanna get close to them and then all of a sudden one turns and starts coming at you. You're not so sure you wanna be close to em anymore. It's really that interesting dance that we do in the water out there well anyway, the next shark that I wanted to share with you, one of the four, is the Shortfin Mako, the Mako shark. And I have to say being in the water with all sharks is pretty extraordinary and I love looking at all animals but, there is truly something very special about being in the water with a Mako. I've always found these animals, they tend to be coastal animals but not really close, you don't see them swimming over the bottom. You have to go several miles off shore and try to attract them, difficult to attract. But when you do see em you know they just come in all jacked up just sort of powering their way through the water, just full of muscle. And this was one that I photographed in San Diego, I worked in a few places, San Diego, New Zealand and Rhode Island, for Makos. But this was one in beautiful blue water of the San Diego bite when the sun was shining on a beautiful September day but, these are very scary animals. This is probably the last thing that a yellow fin tuna sees before it's lights out. They are ambush predators. Makos attack from below, they have that big eye that allows them to see very well in deep dark waters and to be able to look up and see those patterns. And then when they see a prey fish they come up and, they'll often bite the tail off of their prey, whether it's Tuna or Marlin or something like that and then wait for it to bleed out a little bit, circle around and then come in and finish it off. And those are the things that are always foremost in my mind when I'm swimming with a Mako and it's nipping at my fins. I've actually switched my fins. I used to have these split fins that looked a little bit like a fish and so now I've gone with something that like two big two by fours on my feet, something that looks very un-fish like. But yeah everything about this animal says predator. It's really built like a torpedo with teeth. Just pure muscle and all about feeding. Now I also wanted to share sort of a little inside baseball story about shark diving. A lot of shark operators over the last few years have taken to using music on their boat to try to attract certain species of sharks. There's places where they do that with Great Whites in Australia, other places for Blue sharks and so forth. But Makos are very elusive. I've been trying to dive with Makos for decades and had very little success. On this story I had some luck but, they are very hard to get to come close to the boat and a lot of times, when they do come close, they're just in for a few seconds or a minute and then they're gone. So I've had my best luck by trying the music thing. I actually went out there and tried music but what I've learned was that the only music that actually works for Makos is this. “I was caught in the middle of a rain road town”

- That's right, AC DC. These are just badass sharks. I mean that's just all there is to it. And I'm not kidding, we've been out there, I've been out in San Diego and New Zealand for days where nothing was happening and I look at my assistant and say you know, time for a little AC DC. And not every time, but a lot of times, you'll see a Mako come and so, this was one in New Zealand which is sort of Mako central or as they call em there Mako. Mako central, there's a lot of em around and there were days where we had maybe a dozen or so around us in the water. It gets a little too crazy when that happens. But even the little ones, this is another one in San Diego. Even the little ones come in with attitude. They're like, they come in hot and they're all fierce and bitty, Makos will just bite things. They obviously don't have hands and they're just all jacked up, it's like they're on cocaine or something. Not that I would know. But, people have told me. But you know, that one had these copepods on its dorsal fin and this is another one, a bigger animal that was swimming down in that beautiful blue water of California and they often get those parasites on their dorsal looks like little streamers kinda hanging off there. But this diving like the tigers, I always do without cages. It would just be impractical to try to get photographs because the animals are so unpredictable, they don't stick around for very long and they would almost never come over to a cage so, you have to sort of be out there in the open and, most times I'm diving alone, because I don't want even one other person in the water that might spook the shark. But sometimes I'll have an assistant in and sometimes he'll carry just a little stick, as sort of deterrent if the animal gets a little too aggressive which has happened a few times but for the most part, they don't do that, they will come in and check you out a little bit. But these are animals that are endothermic. Meaning that they can generate heat in their body. It was Brooke Runnette actually at National Geographic who termed the phrase hot sharks. These are hot sharks because they can generate heat in their body and because of that they can swim into colder water and feed on oilier fish and so forth. But the Mako is also one of the fastest animals in the ocean. A mako shark can swim at bursts of over 45 miles an hour under water, in fast bursts. And you gotta remember, that underwater, the medium is much thicker than in here so that's probably like swimming a 100 miles an hour or something. But extraordinary animals and, in San Diego I wanted to try to hang out near Kelp Patties. In the Kelp forest of California, Kelp, Giant Kelp will often break off and mad up and drift along the coast and its own little ecosystem forms. We get little fish and then bigger fish and sometimes you get Dorado, Mahi Mahi and fish like that. And I spent weeks out there trying to get a picture of a Mako near one and that's where we see hunting. Didn't actually get em predating but I don't think anything like this had ever been made before so, that was a kind of a cool thing as well. But these are the moments I dreamed about right here, when a big ol' mako shark comes in and bites the crap out of my donport. That's heaven. But you know I honestly try to resist the temptation of making scary pictures of sharks because I really don't want to perpetuate that myth and enough damage has been done to sharks over the years. But by the same token I don't wanna sort of portray them as something that they're not. I don't wanna show them as house pets or give the impression that they're cuddly and we can go out and hug a shark because they're not. They're real predators. So I think we have to walk that fine line and show them for what they are but not over demonize them for sure. And with the same story I also wanted to spend some time looking at shark tournaments. Because there's still a lot of this thing going on where there will be these monster shark tournaments held in various places. So this summer I spent a couple of days in Montauk New York where they hold these tournaments for a couple of days and they give prize money for the biggest shark killed. And often times it's a mako or thresher. But you know, I think that the time has past for this kind of thing, when you consider that a 100 million sharks are being killed every year, I don't really think there is a benefit to sort of glamorizing killing these animals. And the two days that I was in Montauk, I saw six sharks come in, no I'm sorry 12, it was six makos and six threshers and every single one of them was a juvenile. Every single one of them wasn't even old enough to reproduce and, I watched them drag these things up on the dock and sort of cut em up. And I saw all these children, these kids that were fascinated with sharks. But, I think it's sort of unfortunate that this is their first seeing of a shark, looking like a slayed dragon just laid there and that the fishermen were some sort of heroes for doing this. And I have no problem with fishing but, I just think the time has passed for this sort of treatment of sharks. And I recognize that not everyone will get to see a shark underwater, probably the way that they should be seen, this amazingly majestic animal. We can appreciate lions and grizzly bears and tigers and so forth. But underwater these animals are just slaughtered and often with little regard so. My hope is that photography can sort of move that forward a little bit in terms of some appreciation. And one of the other things I wanted to do with this story, with video actually was to show the speed of a Mako attacking something. So with the grant from the Geographic Society, I designed with my assistant a Woods Hole Oceanographic, we designed a toll camera system, I found an industrial camera that shot at very high speed. I could shoot at 720 frames a second. We built this toll camera, and I worked with a New Zealand's champion sports fisherman who fished for marlin and he would rig a mullet bait, type of fish called mullet and trail it behind the boat for marlin but he said often times Makos would attack it. So I was there for a couple of weeks but I only got one day where I could do it. So I've got a two minute video with no sound but I'll just have a look at that and show you, this is the first time this has ever been seen of a Mako in high speed attacking something, a mullet. Everything that you're gonna see here happened in about four seconds. But we're shooting so fast that we can play it back at normal speed and it's slow motion. But it was fascinating to see this animal after he latched on, he sort of put his pectoral fins back in a very hydrodynamic way almost trying to use his weight and the speed to break it off. The boat was travelling at about eight knots. And he had no trouble off course firing up and going in and grabbing that bait. But it was interesting to see that behavior, I think researchers, I haven't showed this to scientists yet but I think they'll be interested to see this form that the Mako assumes once he's bitten into the prey. Just a truly remarkable predator for sure. Going for a ride. They can sort of detach their jaws like a Great White as well. I hadn't realized that but you can see it coming out. So pretty amazing behavior from Mako sharks shot at 720 frames per second well, the third in the four species of sharks that I wanna share with you tonight is the Oceanic White Tip shark, a shark that has been listed as the fourth most dangerous species of sharks if you pay attention to such lists. It's an animal that is a true pelagic predator. This animal lives way out in the open ocean, hunts in deep water, occasionally rises to the surface, it's been called the ship wreck shark, because there are sort of infamous stories about them taking out sailors that were ship wrecked that are drifting at sea. But this is an animal that has to be very efficient at hunting. The open ocean has been described as the desert and there's only pockets of life here and there so these animals have to be very very good at what they do. Oceanics tend to be generally in size between nine and 12 feet in length. And they have those beautiful long pectoral fins, not unlike the Thresher or the Blue shark that we saw but even longer. Their scientific name, their Latin name is Longamanus which when translated means the long hand or the long fingers, which is an apt description. You can imagine an animal like this, swimming up toward the surface and then just gliding down. Maybe a mile deep into the ocean, looking for prey. Completely effortlessly with its pectorals, those dermal denticles, completely hydrodynamic just swooping in silently and nailing some deep water fish. Very efficient predator and this one as you can see is kinda, find it beefy, kind of fat so there's no problem getting food. This is an image I made that shows that distinct shape, the silhouette shape. This was in a place called Cat Island in the Bahamas. And it was back in 2006 that I did an expedition there as part of a story I was doing for National Geographic because we had heard some fish tales about oceanic white tips being seen there. Now oceanics hadn't been seen. I didn't know any diver that had seen one in 20 or 30 years in the Bahamas. But these sport fishermen said they were catching yellow fin tuna and as they were reeling in the tuna, they said that oceanics were stealing the fish off their line. So on that gamble I went out there for 16 days and in 16 days only found one. But I brought a cage along because we didn't know what we would find, this is West Pradish our biologist inside. Turns out we were there at the wrong time of year but if you go at different times of year you can see more oceanic white tips. But oceanic white tips, as recently as about 1970 or in the early 70s were described as the most abundant large animal on the planet. Most abundant large animal, large meaning anything bigger than a hundred pounds. So think about that, there must have been zillions of em out there. Today they're 99% in decline. They're on the verge of extinction. Largely because of their fins. Their fins are highly priced in shark fin soup. So to put this in a little context, to give you some idea, I wanted to show a little bit about an old friend of mine, Peter Gimbel who is a legendary film maker, he was the first guy to dive the Andrea Doria. But back in 1971 he released a theatrical film called Blue Water White Death. Which I think is probably the greatest shark documentary ever done. And it was a film about looking for the great white shark. And he went to different places. And one of the places he went was South Africa where they were hunting whales, they were hunting Sperm Whales at the time. And he went out there with cages trying to find the Great White. But what he found was just tons of Oceanic White Tips. Now I was in South Africa recently for my Tiger Shark story and they don't see oceanics at all. They haven't seen them in a very very long time. So I have a little clip from Blue Water White Death just to put that in perspective, to show Gimbel out there and the kind of violence.

- [Gimbel] Our first dive, a hundred miles at sea. 6000 feet to the bottom. A white tip oceanic surrounded by pilot fish. Sound travels 4 1/2 times faster under water than in air and it carries far. The death throw vibrations of the whales attract sharks from miles away. As the sharks approach, they pick up the blood scent and follow that to its source, where finally, they're guided by sight. Sharks of the open sea, like these, have no air bladder to boil them and they must keep moving all their lives or sink. Sharks are a very successful form of life, they've changed little in a hundred million years. They always seem to bump before they bite. It looks like a test to see how much resistance they're going to run into. These sharks are eight to 12 feet long and weigh up to 1200 pounds. With this amount of food in the water, we expect the Great White. But he doesn't come.

- You know some historical perspective I mean, it's just incredible if you're a diver to see something like that is extraordinary. You just don't see that anywhere in the world. But Cat Island in the Bahamas is one of the only remaining pockets of oceanic white tips that's left in the planet. You can find them in Hawaii, a little bit, sporadically. You can find them in the red sea, but this is really one of the only concentrations. This is my friend Jerome Arrow, a shark camera man swimming with one of them here. So it's one of the only places you could go to photograph them and for this story, it's where I spent my time. We have two of em here, it's like one is saying to the other one, don't look now but there's a guy taking our picture over there. But, it's all done with free diving, we're not using scuba with this, we're just snorkeling. Mass snorkeling fins in a wet suit. And it can get a little interesting when there's several of em around, there's three in this particular frame, especially when the ocean is a little rough, they'll come in and oceanic white tips, as Gimbel mentioned, will often bump. I've never seen their teeth but unlike some of the other species that are a little bit more standoffish, they are quite curious and they will come in and bump. And when they do that nictitating membrane, that white membrane goes over their eye to protect them. So if they were attacking prey that might scratch their eye, it's an evolutionary thing that they've developed. But beautiful animals. And on one of my last days there, I photographed this pair. And the one in the foreground as you see, has a satellite tag on it near the dorsal fin. And these are researchers that have begun to tag these animals and try to track their movements, they don't stay at Cat Island. And we're not quite sure I think where they're going so, we need to know that information if we're gonna be able to protect them. Bahamas has protected all sharks which is a very good and progressive thing to do but if they go somewhere else and get killed, that wouldn't be good so, it's gonna be helpful to have that sort of information. So I have another little video of what it's like diving at Cat Island with me here, oops, maybe we don't.

Dive into the ocean depths with legendary underwater photojournalist and National Geographic explorer Brian Skerry as he shares recent photographs and stories about one of the most fascinating and threatened creatures on the planet: the shark.

The National Geographic Live series brings thought-provoking presentations by today’s leading explorers, scientists, photographers, and performing artists right to you. Each presentation is filmed in front of a live audience at National Geographic headquarters in Washington, D.C.